Method and apparatus for separating foreign material from fine fibers



July 4, 1950 R. A. FAIRBAIRN METHOD AND APPARATUS FOR SEPARATING FOREIGN MATERIAL FROM FINE FIBERS Filed on 25 1949 ear/tor Ho ert A.

Patented July 4, 1950 METHOD AND APPARATUS FOR SEPARAT- ING FOREIGN MATERIAL FROM FINE FIBERS Robert A. Fairbairn, Needham, Mass.

Application October 25, 1949, Serial No. 123,354 In Canada July 11, 1946 3 Claims.

1 This inventionr'elates to the removal or partial removal of foreign material from cashmere, camels hair, vicufia and other animal fibers and 1 from cotton and other vegetable fibers, and it is in the nature of an improvement upon or modification of the inventions disclosed in my United States Patents No. 2,420,035, 2,420,036, 2,420,033 and 2,420,034. This application is a continuation-in-part of my copending application Serial No. 706,488, filed October 29, 1946.

The invention will be explained with particular reference to removing coarse, stiff fibers (beard hairs) from cashmere, although it will be apparent to persons skilled in the art that it is equally applicable to (i) removing coarse, stiff fibers (beard hairs or kemp hairs) from camel's hair, vicufia, wool or other textile fibers comprising fine, crimpy fibers and relatively coarse, stifi fibers and (ii) removing blotches of branding paint, burrs, vegetable defect, straw and other foreign material from wool or other animal fibers and from cotton and other vegetable fibers. When used in this specification and in the appended claims the term foreign material" includes kemp hairs, beard hairs, blotches of branding paint, burrs, straw and other vegetable defect as well as sections, fragments, or pieces thereof.

The principal object of this invention is to provide novel method and a novel apparatus for separating foreign material from a mixture of foreign material and fine fibers.

A further object is to provide such a method and such an apparatus which is economical in operation and in construction.

Further objects will be apparent from a, consideration of the following description and of the annexed drawing in which one embodiment of my apparatus is chosen for the purpose of i1- lustration.

In the drawings:

Fig. 1a is a diagrammatic view in elevation, illustrating one embodiment of appropriate mechanical apparatus elements adapted to perform one embodiment of the method;

scoured for the purpose of removing as much sand, dust, vegetable defect and natural grease as possible. The steps of scouring and dusting are not necessary but are preferred.

The stock is then fed to a machine which is adapted to open up the fiber and pull apart the matted tips for the dual purpose of releasing additional entrapped impurities and disposing the fiber over the width of the machine in an increasingly thinner web or film as it progresses along the length-of the machine from feed to delivery. Such a machine may be a card or a Fig. lb is a diagrammatic view in elevation,

garnett into which may be incorporated the special coarse fiber removing devices and motions that are in part the subject of this invention.

Referring to Fig. 1a, the feed is designated generally by the numeral H). The feed consists of a, hopper H, a spike apron l2, reciprocating combs l3 and M, a scale pan iii, a feed apron or conveyor belt l6, feed rolls Ila and ill), a lickerin l8 and a transfer roll l9.

After scouring and dusting, the raw stock. which consists of intermingled coarse stilt fibers, fine crimpy fibers, vegetable defect, dandrufi' and the like, is fed to the hopper H and is carried upwardly by the spike apron l2. The reciprocating comb it reduces the thickness of the layer of stock upon the spike apron returning the excess to the hopper ii. The reciprocating comb l4 loosens the stock from the spike apron and causes it to fall into the scale pan l5.

When a predetermined weight of stock has accumulated in the scale pan l 5, the scale pan bottom walls ,l 5a and l5b are swung outwardly to the dot-dash positions shown in Fig. 1 and the contents of the scale pan is deposited upon the feed apron it. The bottom walls i5c-l5b are then closed and the scale pan is thus prepared to receive another predetermined weight of the stock.

The stock is advanced by the apron it to thefeed roll lib. The feed roll l'lb removes the stock from the apron and carries it to the bite of the rolls i'la-llb. The stock is then advanced to the surface of the lickerin l8 which is a cylinder provided with card clothing. The action of the teeth of the lickerin clothing pulling the stock from the teeth of the rolls Ila-"b is the initial opening action of the apparatus. The lickerin it is rotated at a greater surface speed than the surface speed of the feed apron l6 and of the feed rolls Ila-41b. The ratio may be for example 4 to 1, the surface speeds of the'feed apron and the feed rolls being substantially the same.

The partially opened stock is carried forwardly by the lickerin and is removed from the lickerin by the transformer roll I 9 which is a cylinder provided with card clothing and which is rotated at a greater surface speed than the lickerin l8; the ratio may be of the order of 2 to 1. The thickness of the layer of stock L is reduced by the action of the transfer roll l9 and it is passed or advanced forwardly to the surface of the breaker cylinder 28. This cylinder 20 is provided with card clothing and is continuously rotated in a clockwise direction looking at Fig. 1a. Three sets of workers and strippers 2 Ia--2lb, 22a22b, and 23a23b are mounted above the breaker cylinder 28. These workers and strippers are cylinders provided with card clothing of gradually increasing fineness and, as is customary, they are mounted progressively closer to the surface of the breaker cylinder 20. As the layer of the stock L is advanced forwardly by the breaker cylinder, the stock is further opened up and the thickness of the layer of stock L is reduced by th action of the workers and strippers so that, prior to its removal from the surface of the breaker cylinder by the doifer 94, the stock has been opened up and disposed in a relatively thin even web or film F throughout the width of the face of the breaker cylinder 20, the fine and coarse fibers being intermingled in this web or film and crossing and recrossing each other.

The doffer cylinder 94 is provided with card clothing the teeth of which point in the direction indicated and it is rotated in a counterclockwise direction at a smaller surface speed than that of the cylinder 20; the ratio being of the order of 1 to 10.

98 is a rotary brush provided at its surface with bristles which are relatively stiff and may be about one inch in length. This brush is rotated in the direction indicated and at a surface speed which is substantially greater than the surface speed of the dofier 94. -I have found that the preferred surface speed of the brush 98 is from four to ten times greater than the surface speed of the dofier 94 and within the range of from about 400 to 1200 feet per minute. The brush 90 is as long as the dofier 94 so that it advances the entire width of the film or web F and, as illustrated, the tips of its bristles act on the back of the teeth of the card clothing of the doifer.

The tips of the bristles of the brush 90 engage the crimpy fine fibers while they are on the surface of the cylinder 94 and since the brush 98 is moving at a substantially greater surface speed than the surface speed of the cylinder 94, it straightens the fine fibers, removes them from the retentive clothing of the cylinder 94 and advances them at a greatly accelerated speed. This causes some of the coarse stiff fibers, dandruff, vegetable defect and other foreign material to be thrown downwardly and free from the film or web F substantially at the region of removal of the film or Web from the surface of the cylinder 94.

In this brush and cylinder motion many of the coarse fibers and much of the other foreign material is removed without the loss of an appreciable amount of fine fibers. The amount of the foreign material removed at the region of transfer from cylinder to brush is believed to be a direct function of the percent of the foreign material present in the aggregate and that percent varies widely in different batches of raw stock.

The second brush 82 is provided with slightly stiffer bristles than the first brush 98 and it is rotated in the same direction as and at a greater surface speed than that of the brush 98. The succeeding brushes 83 and 84, each is provided with 4 slightly stiffer bristles than the respectively preceding brush and is rotated in the same direction and at a greater surface speed than that of the respectively preceding brush. The surface speed of the last brush 84 preferably does not exceed 1200 feet per minute and preferably is 608.35 feet per minute or more. The tips of the bristles of one brush acting upon the tips of the bristles of the slower moving preceding brush straightens the fine fibers, removes them from the bristles of the preceding brush and advances them at an accelerated speed, causing many of the coarse stiff fibers and fragments of other foreign material to be thrown downwardly and free from the film or web F. I have found that with a rotating brush acting against a rotating brush a very satisfactory separation results if the surface speed of the faster moving brush is as small as fifteen percent greater than that of the preceding brush.

By transferring the stock from the brush 84 to a cylinder similar to the cylinder 28 or 28, subjecting it to the action of workers and strippers similar to Zia-2 lb, etc. and then passing it through additional brush against brush motions similar to that of the brushes 82, 83 and 84, additional foreign material may be removed if necessary. The number of such brush and brush motions necessary to produce a product which is acceptable for commercial use depends upon the freeness from coarse fibers and from other foreign material required for the proposed commercial use and upon the percent of foreign material present in each batch of stock which is being run.

For example, to produce an end product which is substantially free from coarse fibers from some raw stocks consistent with space economy, it may be desirable to subject the web or film to a coarse fiber gripping process after one or more of the brushing actions. Such a process and apparatus for use therein is disclosed in my copending application Serial No. 706,484, filed October 29, 1946 entitled Method and Apparatus for Separating Fibers. Instead it may be desirable to subject the film or web after partial removal of the coarse fibers to a coarse fiber dividing and separating method in my Patent No. 2,420,033. On the other hand, if the sales price or the proposed use of the product does not preclude the presence of cut fine fibers or the loss of a small percentage of fine fibers, the remaining fibers may be subjected to the cutting and separating operations hereinafter described.

The cylinder 28 is provided with card clothing and is rotated in a clockwise direction at a greater surface speed than that of the brush 84; the ratio may be of the order of 2 to,1. Three sets of workers and strippers 2911-291), 30a-30b and 3la-3lb are mounted above the cylinder 28. The workers 29a, 30a and 3m are driven at a slower surface speed than that of the cylinder 28; the ratio may be of the order of 1 to 15. The strippers 29b, 30b and 3!?) are driven at a faster surface speed than the workers; the ratio may be of the order of 5 to 1. The action of the cylinder 28 and the workers and strippers is to straighten out the crimpy fine fibers and to rearrange them (together with any remaining coarse fibers) in the form of a relatively thin web or film; they are disarranged from the form of a thin web or film by the action of the brush 84 throwing the fibers into the teeth of the cylinder 28.

The dofier cylinder 32 removes the film or web F from the surface of the cylinder 28 and the reciprocating dofl'er comb It removes the film from the surface of the dofler cylinder 32. If the foreign material has been removed suiliciently for the desired use the film or web may be collected at this point. If it is to be subjected to another series of brush against brush motions it may be transferred from the cylinder 28 to another series of cylinders and brushes similar to M, 90, 82, t3 and Ill. If it is to be subjected to a selective cutting or dividing action. it may be deposited by the doffer comb 83 upon the surface of the conveyor belt 34 and conveyed to one of the selective cutting or dividing apparatus described and shown in my said Patents 2,420,033 to 2,420,036.

As illustrated in Figs. 1a and 1b the film or web F is deposited by the doifer comb 33 upon the smooth surface of the conveyor belt 34 which is suitably supported by and driven by the rolls 35, it and 37. The web or film F is carried by the upper run of the conveyor 34 to the fiber cutting apparatus 38. This cutting apparatus may be of substantially the same type as that more fully described and illustrated in my Patent No. 2,420,033 except that it is designed to out completely through both the fine and the coarse fibers engaged by the cutting elements and the cutting elements are spaced a greater distance apart.

The dividing apparatus 38 comprises a rigid roll 39 having a smooth, hard surface which cooperates with the roll Ml. The roll ill is mounted in suitable bearings capable of micrometer adjustment, so as to vary the distance between the peripheries of the rolls 39 and 40, the surface of the roll W is provided with cutting or dividing elements, for example a plurality of steel wires 40a wrapped helically about the surface of the roll to and attached to pins lb or other suitable means. These wires may be of circular cross section, of a diameter of about 0.01 inch and preferably they are spaced apart a distance of from three-quarters of an inch to three inches, the spacing preferably being determined by the average length of a retracted fine crimpy fiber. Camels hair down or fine fiber has an average extended length of about three and one-half inches and an average retracted length of about one and one-quarter inches so that for cutting camel's hair the cutting wires preferably would be spaced a distance of more than one and onequarter inches apart; two inches has been found to 'be satisfactory. The length of coarse camel's hair fibers or hairs varies from one and one-half to five inches and they are normally straight and when a dry card or garnett web or film of intermingled coarse and fine camels hair fibers is passed between the rotary rolls 39 and 40 with the cutting elements spaced two inches apart, the average cut lengths of the coarse fibers is in the neighborhood of two inches and the average length of the fine fibers is greater due to the fact that they are in generally crinkled or retracted condition when passed between the rolls in dry condition. The cutting elements need not be wires, they may be flutes integral with the roll 40, or any other suitable means.

The rolls 39 and 40 are driven in opposite directions and the smooth roll 4| is driven in a counterclockwise direction as shown in Fig. lb. The rolls 39, 40 and 4| are driven at substantially the same surface speed and at substantially the same surface speed as, or at a slightly greater surface speed than, that of the conveyor belt 34.

Another acceptable cutting apparatus and method comprises condensing the web or film F from the dollar 38 into a sliver by any suitable apparatus well known to the art and feeding the sliver to a suitable cutting apparatus provided with spaced cutting elements adapted to out completely through the fibers at spaced intervals. Such a cutting device may also consist of a reciprocating single blade mife. The stiff fibers in the silver are generally straight and extend generally longitudinally thereof, the fine crimp? fibers are generally retracted to a fraction of their extended length and the bulk of the fine fibers emerge from the cutter of greater average length than the coarse fibers providing the distance between each successive cutting operation is greater than the average retracted length of the fine fibers.

, Regardless of the cutting method employed, the mixture of cut coarse hairs, other foreign material and cut fine fibers is passed in the form of a thin film or web to the cylinder Ma and brushes 90a, 82a, 83a and Ma which correspond respectively to the cylinder at and the brushes 9t, 82, B3 and M of Fig. 1a. The fast moving brush 90a acting against the backs of the teeth of the card clothing of the slower moving cylinder 96a engages the fine fibers, straightens them, removes them from the card clothing and advances them at a greatly accelerated speed and this action causes the cut sections of coarse stifi fibers and fragments of other foreign material to be thrown downwardly and free from the film or web; The tips of the bristles of each of the brushes 82a, 83a and Ma acting upon the tips of the bristles of the respectively slower moving preceding brush straighten the fine fibers, remove them from the bristles of the preceding brush and advance them at an accelerated speed, causing many of the coarse stifi fibers and fragments of other foreign material to be thrown downwardly and free from the film or web F.

The brush 55 serves to remove the foreign material and fine fibers from the roll 39 to transl for them to the card clothing of the cylinder 56. The workers and strippers 5Ea51b, Sta-58b and 59a59b and the cylinder 56 rearrange the fibers to the form of a thin film or web and the cylinder advances it to the doffer 94a.

Similarly the cylinder and the workers and strippers Gila-60b, Gilt-Jib and 6211-4212 rearrange the fibers received from the brush 84a to the form of a thin film or web.

Additional brush and brush motions may be added after the cylinder 60 if desired.

The dofier It removes the film or web from the cylinder 60 and the dollar comb ll removes it from the cylinder 10 and deposits it in the container 12.

While I have illustrated four brushes the invention may embody two or more brushes acting against each other and one or more transfer cylinders provided with card clothing may be inserted between each group of coacting brushes to slow down the speed of the web or film between the groups of brushes.

While in the embodiments illustrated in the drawings I have illustrated each of the faster moving separating brushes rotated to move or advance the film or web downwardly at the region of removal of the film or web from the preceding member so that the foreign material falls by gravity to the floor, these separating members may be rotated to move the film or web upwardly at this region and the upwardly directed coarse fibers, dandruff and other foreign material separated from the film or web by the action of the auaaca brushes may be carried away by pneumatic means. It will be apparent from the foregoing that the method and apparatus of this invention is economical in operation and in construction.

While I have shown and described one desirable method and one desirable embodiment of the apparatus embodying m invention, it is to be understood that this disclosure is for the purpose of illustration only and that equivalent forms of the apparatus may be used and the substitution of equivalent method steps may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

I claim:

l. The method of separating foreign material from fine fibers comprising the steps of forming the intermingled fine fibers and foreign material into a web of the character of a web produced by a carding machine, advancing the web at a predetermined speed upon the bristles of a first rotating brush with one side of the-web exposed, concomitantly straightening the fine fibers, removing the web from said bristles and advancing it at an accelerated speed by subjecting the web to the action of the bristles of a second brush rotating at a surface speed which is substantially greater than the surface speed of said first brush whereby much of the foreign material is thrown free from the fine fibers substantially at the region of removal of the web from the bristles of said 8 with its longitudinal axis substantially parallel to the longitudinal axis of the first brush and with the ends of its bristles lightly engaging the ends of the bristles ofthe first brush and means to rotate said second brush about its longitudinal axis in the same direction as, and at a greater first brush and conducting said freed foreign material to a locality remote from-the fine fibers thereby topermanently separate it therefrom.

2. Apparatus for separating foreign material from fine fibers comprising a first rotary brush having bristles extending radially thereof, means to rotate said brush about its longitudinal axis,

means to form the fine fibers and foreign material into a web of the character of a web produced by a carding machine, means to continuously advance the web to the bristles of said first brush,

a, second rotary brush having bristles extending radially thereof, said second brush being mounted fibers from the first ram-face speed than the surface speed of said first brush, whereby the ends of the bristles of the second brush straighten the fine fibers, remove them from the first brush and advance them at an accelerated speed and much of the foreign material is thrown free from the fine fibers at the region of removal of the fine fibers from the first brush.

3. Apparatus for separating foreign material from fine fibers comprising a first rotary brush having bristles extending radially thereof, means to rotate said brush about its longitudinal axis, means to form the fine fibers and foreign material into a web of the character of a web produced by a carding machine, means to continuously advance a web of mingled fine fibers and foreign material to the bristles of said first brush, a second rotary brush having bristles extending radially thereof, said second brush being mounted with its longitudinal axis substantially parallel to the longitudinal axis of the first brush and with theends of its bristles lightly engaging the ends of the bristles of the first brush, the bristles of the second brush being stiffer than the bristles of the first brush, and means to rotate said second brush about its longitudinal axis in the same direction as, and at a greater surface speed than the surface speed of said first brush, whereby the ends of the bristles of the second brush straighten the fine fibers, remove them from the first brush and advance them at an accelerated speed and much of the foreign material is thrown free from the fine fibers at the region of removal of the fine brush.

ROBERT A. FAIRBAIRN.

No references cited. 

1. THE METHOD OF SEPARATING FOREIGN MATERIAL FROM FINE FIBERS COMPRISING THE STEPS OF FORMING THE INTERMINGLED FINE FIBERS AND FOREIGN MATERIAL INTO A WEB OF THE CHARACTER OF A WEB PRODUCED BY A CARDING MACHINE, ADVANCING THE WEB AT A PREDETERMINED SPEED UPON THE BRISTLES OF A FIRST ROTATING BRUSH WITH ONE SIDE OF THE WEB EXPOSED, CONCOMITANTLY STRAIGHTENING THE FINE FIBERS, REMOVING THE WEB FROM SAID BRISTLES AND ADVANCING IT AT AN ACCELERATED SPEED BY SUBJECTING THE WEB TO THE ACTION OF THE BRISTLES OF A SECOND BRUSH ROTATING AT A SURFCE SPEED WHICH IS SUBSTANTIALLY GREATER THAN THE SURFACE SPEED OF SAID FIRST BRUSH WHEREBY MUCH OF THE FOREIGN MATERIAL IS THROWN FREE FROM THE FINE FIBERS SUBSTANTIALLY AT THE REGION OF REMOVAL OF THE WEB FROM THE BRISTLES OF SAID FIRST BRUSH AND CONDUCTING SAID FREED FOREIGN MATERIAL TO A LOCALITY REMOTE FROM THE FINE FIBERS THEREBY TO PERMANENTLY SEPARATE IT THEREFROM. 